"I can't find one person who has been using the Nexus 7 for an extended period of time, and hasn't seen a massive downgrade in performance. Just what kind of downgrade are we talking here? I cannot pick up my Nexus 7 without experiencing problems like a lag of ten seconds, or more, just to rotate the display; touches refusing to acknowledged; stuttering notification panel actions; and unresponsive apps." Fully and utterly agreed. My Nexus 7 was blazing-fast and awesome for a few months, and at some point, it just started sucking. Just like that. I've tried loads of ROMs, and nothing helps.

Not sure what is the problem, however, if it's shitty filesystem or shitty storage used in the device. I think it is not Nexus 7 specific, and I would blame filesystem in that case.

Actually, I think it's a Nexus 7 specific issue and the type of solid state storage that Asus is using. It's a shame too, because the Nexus 7 is still the best 7" Android tablet you can get. Everybody else seems to be in a race to the bottom, trying to outdo it in price.

Not sure what is the problem, however, if it's shitty filesystem or shitty storage used in the device. I think it is not Nexus 7 specific, and I would blame filesystem in that case.

The cheap controllers in cheap flash devices are notorious for being bad with traditional filesystems like ext4. Some are better with FAT, but they generally have to special case FAT to perform adequately, and even then assume you're writing big files (like jpeg, music or movie files.)

This article gives more information on the challenges of making cheap flash work fast:

Basically, because cheap flash is optimized for large, contiguous writes (writing large media files) general purpose filesystem access suffers unless it is also decomposed into large contiguous writes. This is what log structured filesystems like NIFLS2 and F2FS do, and reap the performance benefits of doing so.

As an example, my Acer Aspire One (the original 8GB SSD one) runs completely from a cheap plugin 32GB USB FLASH module, using NILFS to decompose the random writes into large contiguous writes. While NILFS is no performer compared to other FS on general purpose SSD, it trounces the likes of ext4 on cheap media like this, and keeps the netbook usable.

What I suspect 'Forever Gone' is doing is either:

- Triggering TRIM to the underlying device, if it's supported.
- Writing all zeros to the underlying device, which
the device can optimize by not actually storing, but simply marking the blocks as containing all zero data.

Either way, the underlying device can discard what would otherwise be useless data, and keep lots of clean FLASH blocks free.

Hopefully, if F2FS or NILFS become mainstream, these sorts of problems should be a thing of the past.

I might be that one person that hasn't seen any performance downgrade. I wouldn't call myself a "power user" (my rooting/flashing days are long gone), but I do use it almost every day, more now than before as a matter of fact.

Don't have that many apps or media installed on mine unit (still 8GB+ free), so that might be why I'm not having problems.

Mine has never skipped a beat. I recently bought a Nexus 10 more as a size issue, and my Nexus 7 is now serving faithfully for my brother. It may be important that it's been reflashed twice, just because I could. Once with the Ubuntu preview, and again back to stock.

I just got one the other day in a trade with a friend (he needed a laptop RIGHT NOW for a work project, he wasn't using his Nexus anymore, I wasn't using my Sony laptop anymore). I am blown away by both the speed and fluidity of JB on this device, and the utterly boring Android interface (not a complaint!). I know I could try a different ROM or launcher and get a "better" experience but I actually enjoy the simplicity of it.

I may try Ubuntu on it one day -- its high compatibility with that OS is what sparked me to make the trade -- and if this "slowdown" ever starts happening to the device I may just switch to that or even Firefox OS. As long as I can read my ebooks and browse the occasional website I'll be happy, as that is all I use a tablet for.

I bought a nexus 7 a month or 2 after launch , 3-4months ago the charger pin was damaged and it would not charge anymore. I called Google support to get it replaced, so maybe since my current device is much newer, that's why I don't notice anything. Even so, the previous device never lagged either.

This has indeed very much been my experience with my Android devices (Hero and Arc). They start out fast and reasonably fluid, and then somehow degrade over time. A reset fixes things, which I think is a large part of why with every custom rom a lot of people go "finally, it is running perfectly now!", only to not post when things degrade again a month later.

I see posts above suggesting that it is a flash storage issue specific to the Nexus 7, but I have to think, from my own personal experience, that this is something a lot of Android devices suffer from. I have no real clear theories why, but unfortunately it is one of those things that are impossible to tell in the store or upon the first-impressions review on crowdsourced websites, so it is a slightly hidden problem with a lot of devices.

I ended up on WP8 myself this time, which is a deeply flawed OS, that does, however, thrill me a bit with fantastic fluidity every time I pick up the phone, even 6 months after I first got it.

Google has confirmed that the device needs to have a couple of gigs free in order to function fluidly. There was a columnist in some website (pcmag, pcworld, wired, can't remember) complaining about that. Too lazy to find the link.

Android is a junk OS, sorry fans. It consumes CPU and battery with a huge appetite, and it needs to "have some free space left" otherwise things get slugish (the Unix Haters Handbook wants it's lame filesystem back, seriously it had a complaint about that exact problem)

Also, all those adverts claiming "16GB" or "32GB" of storage without clarifying how much of it is free and how much of it you can fill up without slowing things to a crawl make some telemarketing frauds look like totally honest adverts. 'Till the class action lawsuit happens, things will get worse.

It's a hardware issue. ASUS skimped on storage(did not include a proper buffer, like the 240GB SSDs actually have 256GB). The OS is not junk, just because the hardware manufacturer did not include something that the OS expects.

The OS is not junk, just because the hardware manufacturer did not include something that the OS expects.

Risking an OS war a bit, but shouldn't a mobile OS (like Android) have a filesystem designed specifically for flash storage (with a trim command and all), instead of using a filesystem designed for spin-up magnetic drives (ext4), and ask from the hardware to emulate a spin-up magnetic drive for it?

Generally, Android feels like a resource hog. It has the random slowness issue (everything runs fine, then suddenly everything slows down to a crawl for a couple of seconds, then everything is fine again), it consumers lots of battery, it occupies a ton of space because it needs seperate physical partitions for programs and user files like back in the days of old Unix (this is why the Galaxy S4 has so little user space, the rest of the internal storage is for apps).

Don't get me wrong, I admire Android for being the only true PDA from the big 3 (WP, iOS, Android), I just wish Google did more designing and less hacking.

Risking an OS war a bit, but shouldn't a mobile OS (like Android) have a filesystem designed specifically for flash storage (with a trim command and all), instead of using a filesystem designed for spin-up magnetic drives (ext4), and ask from the hardware to emulate a spin-up magnetic drive for it?

Really, I don't think it's fair to single out Android on this front. iOS is BSD-based, and WP8 is Windows NT based, so that only leaves Blackberry's QNX-based OS as a relatively successful mobile platform whose internals are potentially optimized for embedded needs.

Generally, Android feels like a resource hog. It has the random slowness issue (everything runs fine, then suddenly everything slows down to a crawl for a couple of seconds, then everything is fine again), it consumers lots of battery, it occupies a ton of space because it needs seperate physical partitions for programs and user files like back in the days of old Unix (this is why the Galaxy S4 has so little user space, the rest of the internal storage is for apps).

Again, once you have played with the old generation of mobile OSs which were truly optimized for slow processors, small amounts of storage, and long battery lives, all newer mobile OSs feel like a waste of resources.

The main issue with Android is that it makes the inadequacy of using desktop kernels in embedded systems more obvious, by letting users and software take advantage of low-level features which are particularly ill-designed for modern needs, such as multitasking.

Also, Android is often scaled down to lower-end hardware than iOS and WP8, which further emphasizes the serious task prioritization and performance issues that its Linux internals exhibit. If iOS provided developers with similar access to its low-level functionality, you could bet that the situation would not be much different from the Android one.

On flash-based SSDs, you cannot truly overwrite data, only erase it (which is a lengthy process) and rewrite.

Most SSDs deal with this by implementing some form of garbage collection, in which the drive controller silently erases unused block in the background when it is not requested data. However, this only works as long as there are some blank blocks available when a write is to be performed. If data has to be written and no blank memory blocks are left, then the drive has to wipe some memory blocks before it can perform the write, which dramatically slows some things down.

Some drives address this by actually having more memory blocks available than the advertised storage capacity, which is also a good strategy to manage bad storage blocks. For this latter reason, such a strategy was already used in the HDD era.

Of course, as you mention in another comment, this wouldn't be an issue if Unices weren't so reliant on synchronous HDD writes to begin with.

Windows and OS X also tend to get slow when you fill up all the disk space

Because they run mostly on spinup drives, so as the hard drive fills up, finding unfragmented free space becomes harder. And the writes happen on the inner rings which are slower, and any new updates/installs get written on the inner rings. An OS that runs on flash storage and runs a filesystem designed for flash storage (with trim commands visible to the OS), shouldn't get much slower when the drive fills up.

Can't believe no one's suggested the most obvious reason for these slow downs. Forget plausible possibilities like filesystem clogs, and Trim implementations..

It's obviously after around this length of time, depending of course upon how quickly you've racked up a suitable keyword quotient, that the NSA monitoring machine will have picked you up, logged you as monitor worthy - and will presently be 'logging on' to your device and installing keyloggers, decryptosomes and all sorts..! Which necessarily slow things down 25-75%